Tuesday, May 22, 2012

Initial Field Test Results

At this point in time, one beta tester has tested the J-head Mk V. For a total of at least 6 hours, PLA was printed successfully. He is going to try to print ABS in the near future.

There were two minor issues encountered early on, however. The first issue was that the hot-end jammed. This was theorized to be due to dirt and the hot-end was cleaned out. Afterwards, it printed fine. The second issue was that some PLA was leaking out of the hot-end. After the set-screw was tightened down, the leaking stopped.

As both issues were relatively minor, and were easily fixed, the initial results are fairly positive.

The Mini J-head has also been successfully tested printing PLA and no issues were reported.

12 comments:

Any reference to the speed of printing in the above test, and if ooze is reduced or worse than before.I would be interested to know if the smaller thermal mass of the block allows slower and more fine printing (less ooze) or if it also limits the maximum speed of the nozzle compared to the IV.

The Mini J-head was printing at 183 mm/sec and the Mk V was printing at 140mm/sec. The Mk V wasn't tried at higher speeds. The mini J-head was tried at 200mm/sec. and there were issues with the stepper motor slipping.

There was no mention about the ooze being different.

The weights, of 3 different brass nozzles are as follows:1. Version 1--11.1 grams2. Version 1.1--14.4 grams (added melt zone)3. Version 4--11.3 grams

The Version 1 and 1.1 can be used for the Mk I through Mk IV hot-ends while the Version 4 is used with the Mk V-B hot-end. While the Mk V-B uses a smaller piece of brass, it has a longer melt zone and a thicker brass wall, for the melt zone. The idea was to keep a thick brass wall in order to increase the thermal mass.

On which platform did you reach 140 mm/s ?My prusa-mendel i2 doesn't allow +40, but I blame that on not being sturdy enough. Perhaps bracing it, or going for another platform in the future. Happy for now (though my Mk IVb seems to be jammed somehow)

How are the mini J-Heads coming along? I have a printer under assembly, with nearly all the parts either on hand or on order. Just need a lightweight hot end for 1.75mm filament for it, and I'd prefer to use the mini J-head over the Makergear hot end.